The invention relates to a conveyable-article carrier for transporting conveyable articles along a conveying section in a conveying apparatus, in particular a suspended conveying apparatus, which has running rails for guiding conveyable-article carriers and also has a drive belt which is guided along the running rails and is intended for carrying along the conveyable-article carriers along the conveying section, it being the case that each conveyable-article carrier has a carrier body and a coupling element which is located on the carrier body and is intended for being brought into drive connection with the drive belt, it being the case that the conveyable-article carriers can also be accumulated in at least one build-up region of the conveying apparatus, as the drive belt continues running, and each have a separating device which can be activated under the action of the build-up pressure and is intended for temporarily releasing the drive connection.
A conveyable-article carrier and a conveying apparatus of the abovementioned type are known, for example, from EP-0 623 497 B1. These known conveyable-article carriers are so-called hanger carriers for transporting items of clothing hanging on clothes hangers in a suspended conveying apparatus. During conveying operation, the hanger carrier is suspended laterally on a running rail of the conveying apparatus by way of one of two running rollers which project from the carrier body symmetrically to the vertical center plane of said hanger carrier, the running roller being guided on a running surface of the rail for movement in the longitudinal direction of the rail. Beneath the running rollers, symmetrically to the vertical longitudinal center plane, two rigid protrusions project laterally from the carrier body, the outwardly oriented surfaces of said protrusions being designed as frictional surfaces for a frictional-belt drive. During conveying operation, the frictional surface which is directed toward the running rail in each case is in drive connection with a frictional belt which runs in a guide of the running rail, in the longitudinal direction of the rail. The frictional belt, which is moved along the rail, carries along the conveyable-article carrier via the frictionally locking coupling between the frictional surface and frictional belt, and the running roller of the conveyable-article carrier, said roller being guided on the rail, rolls on the running surface of the running rail.
The known suspended conveying apparatus is a power-and-free conveyor which is capable of accumulation and in the case of which a group of similar conveyable-article carriers can be accumulated in a build-up region as the frictional belt continues running. In order to avoid the situation where the frictional surfaces of the accumulated conveyable-article carriers rub against the frictional belt as it continues running, the known conveyable-article carrier has a separating device for temporarily releasing the drive connection. Said separating device comprises, on both sides of the vertical center plane, in each case one resilient tongue which can be spread laterally from the carrier body and is provided at a relatively large vertical distance from the running rollers beneath the frictional-surface protrusions. In the spread state, the resilient tongue is supported on an abutment surface of the running rail, the conveyable-article carrier being pivoted by a small amount relative to the running rail such that the frictional surface is freed from the frictional belt or at least butts against the frictional belt with reduced abutment pressure. The resilient tongue is spread under the action of the build-up pressure, an adjacent conveyable-article carrier in the build-up in each case forcing the resilient tongue outward into the spreading position by way of a spreading mandrel. A disadvantage of this known conveyable-article carrier is that comparatively high forces are necessary in order to pivot the hanger carrier as a whole such that, in the build-up arrangement, it is reliably freed from the frictional belt. In particular by virtue of the conveyable articles which are to be transported having a relatively high dead weight, the forces which are necessary for disconnecting the hanger carrier are of such a magnitude that they can only be applied with a considerable build-up pressure of a relatively large number of advancing hanger carriers. The forces for disconnecting, i.e. for pivoting the hanger carriers relative to the running rail cannot be defined particularly well on account of the dependence on the dead weight of the conveyable-article carrier, with the result that the disengagement from the frictional belt, which is required during build-up, does not always take place reliably and often only takes place with delay, that is to say once a sufficiently high build-up pressure has been produced. With delayed or incomplete disengagement of the conveyable-article carrier from the frictional belt, there is a risk of increased wear to the frictional surface and of pronounced heating by frictional heat both on the hanger carrier and on the frictional belt. Furthermore, the rubbing of the frictional surfaces subjects the frictional belt to more pronounced loading, with the result that the frictional-belt drive has to be dimensioned such that it can overcome such loading. Added to this is the fact that the frictionally locking coupling of the conveyable-article carrier to the drive belt during conveying operation depends to a great extent on the dead weight of the conveyable-article carrier.
The object of the present invention is to provide a conveyable-article carrier of the type mentioned in the introduction of which the separating device functions reliably for temporarily releasing the drive connection irrespective of the loading to which said carrier is subjected by the dead weight of the conveyable articles.
In order to achieve this object, the invention proposes that, in the case of the conveyable-article carrier, the coupling element be designed as a part of the separating device which can be moved relative to the carrier body between a drive position, for coupling to the drive belt, and a neutral position, for disengaging from the drive belt.
In contrast to the conveyable-article carrier according to the prior art, it is not necessary for the conveyable-article carrier according to the present invention to be moved as a whole transversely to the running rail for disengagement from the drive belt; rather, it is essentially only the coupling element which needs to be moved for this purpose. The movement of the coupling element between the drive position and the neutral position may be brought about by comparatively low, and in particular, defined forces, with the result that, in the case of a build-up, a low build-up pressure is sufficient in order to disengage the conveyable-article carrier reliably from the drive belt. This means that operation of the conveying apparatus fitted with the conveyable-article carriers involves less destruction.
The coupling element is expediently prestressed resiliently in the direction of the drive position, with the result that it can be moved into the neutral position counter to the spring prestressing. The prestressing may be applied, for example, by means of a straightforward helical spring. Appropriate selection of the spring allows the force which is necessary for disconnecting the conveyable-article carrier to be very well defined.
The separating device preferably has an actuating element for the coupling element, it being possible, in the case of a conveying build-up, for the actuating element to be actuated under build-up pressure by an adjacent conveyable-article carrier in the build-up in order to move the coupling element into the neutral position. In conjunction with this, it is proposed that the separating device has a disconnecting element which, in the case of a conveying build-up, can pass into engagement with the actuating element of a similar, directly adjacent conveyable-article carrier in the build-up in order to move the coupling element thereof into the neutral position. The conveyable-article carrier is thus of such a nature that, in the build-up arrangement, it is disconnected automatically from an adjacent conveyable-article carrier.
Although the invention can be used for conveyable-article carriers for chain conveyors with a chain as the drive belt, the preferred embodiment of the invention relates to a conveyable-article carrier for a conveying apparatus in which the drive belt is a frictional belt, the coupling element of the conveyable-article carrier having a frictional surface which is to be connected to the frictional belt with frictional locking in order to produce the drive connection. The advantages of the invention are evident, in particular, in conjunction with such a frictional-belt drive. The reliable and rapid disengagement of the conveyable-article carrier from the frictional belt in the case of a build-up ensures that the frictional surface is not adversely affected and that excessive heating of the conveyable-article carrier and of the frictional belt is avoided. Since accumulated conveyable-article carriers according to the invention do not rub against the frictional belt as it continues running, the frictional belt may be driven by a relatively small-dimensioned and inexpensive drive motor.
A preferred embodiment of the invention provides on the conveyable-article carrier at least one laterally projecting running roller for the suspended support and guidance of the conveyable-article carrier on a running-profile surface of the running rails of the conveying apparatus, it being the case that the frictional surface of the conveyable-article carrier, which is suspended on the running-profile surface by way of its running roller, is located opposite the frictional belt and, with the coupling element located in the drive position, is displaced laterally outward relative to the carrier body, with the result that it is in frictionally locking connection with the frictional belt. As the coupling element passes from the drive position into the neutral position, the frictional surface moves in the direction of the carrier body in order to be freed from the frictional belt.
In the case of a separating device which can be realized relatively straightforwardly, the coupling element can be pivoted relative to the carrier body between the drive position and the neutral position about an essentially vertical pivot axis, the coupling element preferably being provided on one lever arm of a two-armed lever which can be pivoted about the pivot axis and of which the other lever arm is designed as the actuating element for the coupling element. Such a lever design constitutes an uncomplicated and reliably functioning coupling-element actuating mechanism which can be activated by an adjacent conveyable-article carrier in the build-up.
In the driven state, the conveyable-article carrier is intended to be carried along by the frictional belt with as little slippage as possible. In order to ensure this, it is proposed that the coupling element be provided with a rubber coating which has the frictional surface.
According to a particularly preferred embodiment of the invention, there is rotatably mounted on the carrier body at least one lateral supporting roller by means of which the conveyable-article carrier can be supported laterally on a vertical side surface of a respective running rail of the conveying apparatus.
The supporting roller ensures that the conveyable-article carrier is in defined alignment with the running rail irrespective of the loading to which it is subjected by the dead weight of the conveyable articles which are to be transported. This ensures that, during the movement between the drive position and the neutral position, the coupling element always has to cover the same path, and that the contact-pressure force, which is applied by a spring and is exerted on the frictional belt by the frictional surface, and the force which is necessary for disconnecting the hanger carrier are very well defined.
In a modified embodiment, the spacer function of the lateral supporting roller may be performed by a protrusion which projects laterally from the carrier body and slides on a relevant abutment surface of the running rail.